The present invention relates to a striker mechanism for a high speed serial printer, including a hammer movable with respect to a fixed guide in the direction of the platen of the printer. The striker mechanism is particularly useful in a printer of the daisy wheel type, which can be mounted on a typewriter, an automatic text printer, an accounting machine, a teleprinter or any similar printing machine.
In this type of high speed printer, in which the frequency of the printing cycle is very high, one of the technical problems to be resolved is that of eliminating the vibrations of the printing hammer and of reducing to the minimum the settling time of the whole striker mechanism after the printing of a selected character, in such a way as to perform a new printing cycle immediately after the preceding cycle.
In a known striker mechanism, for damping the oscillations of a printing hammer, the hammer is connected to a pawl engageable with a ratchet wheel rotatable between two friction discs. In this way, when the hammer turns towards its rest position, the pawl makes the ratchet wheel rotate against the action of the friction discs, which act as dampers for the hammer. The pawl does not act on the ratchet wheel during the striking action of the hammer but only during its movement towards the rest position. This mechanism therefore only partly solves the technical problem discussed above since it does not eliminate the oscillations about the stopping position, still less the intrinsic vibrations of the hammer.